Failure in deinterlacing?

Help/How To
20

It’s fundamentally working. Congratulations!
Needs refinements and easier operation. All problems I faced and report here below, seem only due to the implementation as pre-conversion. That’s why let me first give my suggestion:

Suggestion:

Instead of improving the present implementation, you could remove it for the coming release, and target the same thing (it works very good) as an improvement of the deinterlacing which already was implemented. If I understand rightly, the former deinterlacing does not create extra files, so it needs no extra encoding/compressing. And it automatically happens whenever needed, which is a) for export and b) before doing any geometry-affecting filters. In these cases, double rate should not disturb, only improve. Implementing it there will simplify the use a lot, compared to now.

(It will need careful testing by the programmer, and observing the implications mentioned here Failure in deinterlacing?, but I guess it is possible. With e.g. 25p-footage, the timeline could be set to 50 Hz and the export process steps through time in 1/50th, and it has to know that the material was interlaced, which already exists because this triggers the deinterlacer and can do it even before geometry filter.

No idea if the deinterlacer used for geometry filter is also defined by the dropdown choice in export > advanced > deinterlacer. Maybe you can add a choice “doubling rate” to this de-interlace dropdown, or provide a new setting in the general menu with the options to either run deinterlacing as used to, or run all in doubling rate. But maybe this option is not even necessary and all deinterlacing can be done in double frequency. All scenarios seem to match well with the double rate. Only for export into identical interlaced format, deinterlacer should not be used, but if I know rightly, it is already done this way.

Then the user only needs to chose the project frequency, all else happens automatically.

Since the first opened file automatically presets the project standard, interlaced files should then set the project to their field rate, instead of their frame rate. This is the only point for which a setting should be created (to make it an option), so that the new version can behave identical as the old one. For the quality improvement of the new interlace (which is: avoiding identical images in neighbouring frames), a disable option seems not necessary.

Problems in present Beta-Version (observe only if my suggestion can’t be used):

  1. File size is 10 x larger than the original footage (straight from the camera), even in smallest quality setting, --> Why nor define the quality in relation to the data rate of the original? As default, it should be double, due to the double frame rate. With middle quality, labelled “good”, the result is not usable. File size is 50x larger than original. Windows media player can not play it. VLC player shows complete mess (motion blur). The player of Shotcut can play it, but when pulling it into the timeline, Shotcut crashed sometimes (no response, “inactive” while 0% processor according to taskmanager in Windows 8.1).

  2. Make it easier by removing the “advanced” button in “convert”, and always display all. Otherwise it is dangerous and tricky, because the user is completely unclear if the (hidden) settings are kept or will disappear, and at which occasion this happens, so we have to have it open anyway.

  3. Finding a setting until the export delivers 50 fps seems very complicated. My first try had 50 fps but with images changing in 25 Hz. I got correct result only when during export, de-interlacing is deactivated, which seems not always possible, because it is fixed on YADIF, and in global settings, video-mode is set to 50p /or 60p. But I did not understand the meaning of the tickbox in properties > convert > advanced > “override frame rate”. Maybe it means: match the frame rate of the setting in Main-Menu > “video mode” to the converted result? In this case, the labels could be named better. And it is unclear which purpose has the numeric input for frame rate, and when to use it

  4. Using it in the present way is not easy (like using an external de-interlacer): We have to create separate files for each clip and use more conversion time for the additional enoding/compression step.